It is important for pilots to understand the landing environment when approaching a runway for landing. Approach lights are an important part of this landing environment. Typically, a pilot will see, or recognize, the approach lights well before seeing the runway, especially in limited visibility of night and/or weather, or at unfamiliar airports. Approach lights include many types that vary in length, width, and design. A decrease in pilot workload in gaining this recognition of the approach environment typically results in increased safety: when the information provided on the screen is easily interpreted, freeing more of the pilot's thought processes when he may have many other decisions to make.
Many vehicles, such as aircraft, are commonly equipped with one or more vision enhancing systems to convey flight path and/or flight management information. Such vision enhancing systems are designed and configured to assist a pilot when flying in conditions that diminish the pilot's view from the cockpit, such as, but not limited to, darkness and weather phenomenon. One example of a vision enhancing system is known as a synthetic vision system (hereinafter, “SVS”), which may be more generally described as a being a dynamic condition subsystem of the aircraft. An example of a synthetic vision system is disclosed in U.S. Pat. No. 7,352,292. Additionally, an exemplary synthetic vision system is available for sale under product name SmartView, manufactured by Honeywell International, Inc.
A typical SVS is configured to work in conjunction with a position determining unit associated with the aircraft as well as with dynamic sensors that sense the aircraft's altitude, heading, and attitude. The SVS typically includes a database containing information relating to the topography along the aircraft's flight path. The SVS receives inputs from the position determining unit indicative of the aircraft's location and also receives inputs from the dynamic sensors on board the aircraft indicative of the aircraft's heading, altitude, and attitude. The SVS is configured to utilize the position, heading, altitude, and orientation information and the topographical information contained in its database, and generate a three-dimensional image that shows the topographical environment through which the aircraft is flying from the perspective of a person sitting in the cockpit of the aircraft. The three-dimensional image may be displayed to the pilot on any suitable display unit accessible to the pilot. Using an SVS, the pilot can look at the display screen to gain an understanding of the three-dimensional topographical environment through which the aircraft is flying and can also see what lies ahead. One advantage of the SVS is that its image is clean and is not obstructed by any weather phenomenon.
Thus, SVS images can provide the vehicle operator with an effective interface for vehicle control. SVS image integrity, however, is limited by the integrity of the information pre-stored in the database. Accordingly, incomplete and/or outdated database information can result in SVS images of limited value.
Another example of a vision enhancing system is known as an enhanced vision system (hereinafter, “EVS”), which may be more generally described as being a sensor subsystem. Examples of enhanced vision systems are disclosed in U.S. Pat. Nos. 7,655,908 and 5,317,394. Additionally, an exemplary enhanced vision system is available for sale in the market place under product name EVS-II, manufactured by Kollsman, Inc. A typical EVS includes an imaging device, such as, but not limited to, a visible lowlight television camera, an infrared camera, or any other suitable light detection system capable of detecting light or electromagnetic radiation, either within or outside of the visible light spectrum. Such imaging devices are mounted to the aircraft and oriented to detect light transmissions originating from an area outside of the aircraft and are typically located ahead of the aircraft in the aircraft's flight path. The light received by the EVS is used by the EVS to form an image that is then displayed to the pilot on any suitable display in the cockpit of the aircraft. The sensor used in an EVS can typically see what a human eye cannot, which might be caused by sensitivity to other part of spectra than visible light, or greater sensitivity to visible light than the typical human eye has. Accordingly, using the EVS, a pilot can view elements of the topography that are not visible to the human eye. For this reason, an EVS is very helpful to a pilot when attempting to land an aircraft in inclement weather or at night. One advantage to the EVS system is that it depicts what is actually present versus depicting what is recorded in a database. Although some image processing is commonly used and it can improve image quality, the images presented to the vehicle operator still may not be optimal for pilot workload.
Some display systems display both an SVS image and an EVS image display. For example, an EVS image is displayed that is augmented by an SVS image of terrain surrounding the EVS image; such terrain being out of the field of view of the EVS sensor.
Accordingly, it is desirable to provide an apparatus and method for displaying approach lighting that is readily discernable by the pilot while reducing the pilot's workload. Furthermore, other desirable features and characteristics of exemplary embodiments will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.